I combine ready-made mentsuyu noodle sauce and gochujang for a Korean version.
I received gochujang and used it for this somen dish as I heard that people eat somen noodles in Korea for the Qixi festival.
I serve this sauce to pour over the noodles and not for dipping. It's not that tart, but adding acidity will balance out the flavors. Garnish with your favorite toppings.
Enjoy Japanese food around the world.